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Related papers: Lower Bounds in Real Schubert Calculus

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The Shapiro conjecture in the real Schubert calculus, while likely true for Grassmannians, fails to hold for flag manifolds, but in a very interesting way. We give a refinement of the Shapiro conjecture for the flag manifold and present…

Algebraic Geometry · Mathematics 2010-03-29 James Ruffo , Yuval Sivan , Evgenia Soprunova , Frank Sottile

We introduce the concepts of complex Grassmannian codes and designs. Let G(m,n) denote the set of m-dimensional subspaces of C^n: then a code is a finite subset of G(m,n) in which few distances occur, while a design is a finite subset of…

Combinatorics · Mathematics 2008-06-16 Aidan Roy

Schubert polynomials are a basis for the polynomial ring that represent Schubert classes for the flag manifold. In this paper, we introduce and develop several new combinatorial models for Schubert polynomials that relate them to other…

Combinatorics · Mathematics 2020-03-05 Sami Assaf

We prove lower bounds for the worst case error of quadrature formulas that use given sample points $\X_n = \{ x_1, \dots , x_n \}$. We are mainly interested in optimal point sets $\X_n$, but also prove lower bounds that hold with high…

Numerical Analysis · Mathematics 2020-12-08 Aicke Hinrichs , David Krieg , Erich Novak , Jan Vybíral

We study modular analogues of Schur numbers for systems of linear equations. We show that these only depend on the number of equations, not their coefficients and in the case of one equation show stronger bounds.

Combinatorics · Mathematics 2026-04-28 Tom Sanders

We present the first super-linear lower bounds for natural graph problems in the CONGEST model, answering a long-standing open question. Specifically, we show that any exact computation of a minimum vertex cover or a maximum independent set…

Distributed, Parallel, and Cluster Computing · Computer Science 2017-05-17 Keren Censor-Hillel , Seri Khoury , Ami Paz

We extend the classical Schubert calculus of enumerative geometry for the Grassmann variety of lines in projective space from the complex realm to the real. Specifically, given any collection of Schubert conditions on lines in projective…

alg-geom · Mathematics 2008-02-03 Frank Sottile

We study exceptional minuscule Schubert varieties and provide the defining equations of the defining ideals of their intersection with the big open cell. We also provide the resolutions of these ideals and characterize some of them in terms…

Representation Theory · Mathematics 2020-12-22 Sara Angela Filippini , Jacinta Torres , Jerzy Weyman

Consider the classical problem of rational simultaneous approximation to a point in $\mathbb{R}^{n}$. The optimal lower bound on the gap between the induced ordinary and uniform approximation exponents has been established by Marnat and…

Number Theory · Mathematics 2021-03-11 Johannes Schleischitz

We introduce several generalizations of classical computer science problems obtained by replacing simpler objective functions with general submodular functions. The new problems include submodular load balancing, which generalizes load…

Data Structures and Algorithms · Computer Science 2010-06-02 Zoya Svitkina , Lisa Fleischer

We collect a few guesses on possible implications of a lower bound on the scalar curvature of a Riemannian manifold on the size and shape of this manifold.

Differential Geometry · Mathematics 2017-10-18 Misha Gromov

Let X be an orthogonal Grassmannian parametrizing isotropic subspaces in an even dimensional vector space equipped with a nondegenerate symmetric form. We prove a Giambelli formula which expresses an arbitrary Schubert class in the singular…

Algebraic Geometry · Mathematics 2012-04-02 Anders S. Buch , Andrew Kresch , Harry Tamvakis

Numerical homotopy continuation of solutions to polynomial equations is the foundation for numerical algebraic geometry, whose development has been driven by applications of mathematics. We use numerical homotopy continuation to investigate…

Algebraic Geometry · Mathematics 2008-06-13 Anton Leykin , Frank Sottile

Error bounds have been studied for more than seventy years, beginning with the seminal result of Hoffman (1952) [{\it J. Res. Natl. Bur. Standards}, 49 (1952), 263--265], which establishes an upper bound for the distance from an arbitrary…

Optimization and Control · Mathematics 2026-05-25 Zhou Wei , Michel Thera , Jen-Chih Yao

We consider the problem of determining Gr\"obner bases of binomial ideals associated with linear error correcting codes. Computation of Gr\"obner bases of linear codes have become a topic of interest to many researchers in coding theory…

Information Theory · Computer Science 2017-07-25 Arunkumar R. Patil , Nitin S. Darkunde

We study the numerical bounds obtained using a conformal-bootstrap method - advocated in ref. [1] but never implemented so far - where different points in the plane of conformal cross ratios $z$ and $\bar z$ are sampled. In contrast to the…

High Energy Physics - Theory · Physics 2016-11-04 Alejandro Castedo Echeverri , Benedict von Harling , Marco Serone

We provide a technique to obtain explicit bounds for problems that can be reduced to linear forms in three complex logarithms of algebraic numbers. This technique can produce bounds significantly better than general results on lower bounds…

Number Theory · Mathematics 2023-10-02 Maurice Mignotte , Paul Voutier

We prove a root system uniform, concise combinatorial rule for Schubert calculus of_minuscule_ and_cominuscule_ flag manifolds G/P (the latter are also known as "compact Hermitian symmetric spaces"). We connect this geometry to the poset…

Algebraic Geometry · Mathematics 2010-02-17 Hugh Thomas , Alexander Yong

We describe an approach to the question of finding real solutions to problems of enumerative geometry, in particular the question of whether a problem of enumerative geometry can have all of its solutions be real. We give some methods to…

alg-geom · Mathematics 2008-02-03 Frank Sottile

This article provides new lower bounds for both Schur and weak Schur numbers by exploiting a "template"-based approach. The concept of "template" is also generalized to weak Schur numbers. Finding new templates leads to explicit partitions…

Combinatorics · Mathematics 2022-04-05 Romain Ageron , Paul Casteras , Thibaut Pellerin , Yann Portella , Arpad Rimmel , Joanna Tomasik